Palladium(II) coordination of N-heterocyclic carbene ligands with a triazole moiety in the nitrogen substituent
Abstract
• Synthesis and characterization of Pd(II) complexes with N-heterocyclic carbene ligands having a triazole pendant group. • Characterization of geometrical and rotational isomers for complexes of general formula [PdI 2 (NHC) 2 ]. • Evaluation of the energetics of the different isomers via DFT calculations. • Possibility to functionalize the triazole moiety affording a precursor of triazol-based N -heterocyclic carbenes. • Dinuclear complex formed by bridging coordination through the N-triazole and the C-imidazole atoms to two trans -PdI 2 units. A series of N -heterocyclic carbene (NHC) palladium complexes derived from N -methyl or N -mesityl-imidazolium salts bearing a triazole ring as pendant group to the second nitrogen atom, have been synthesized and characterized by NMR spectroscopy, mass spectrometry and single-crystal X-ray diffraction. Deprotonation of the imidazolium salt with palladium(II) acetate in acetonitrile affords square-planar Pd(II) complexes of general formula [PdI 2 (NHC) 2 ] with trans geometry. The steric hindrance of the NHC ligand substituents allows to characterize in solution both rotation syn and anti isomers. In contrast, in the crystallization process, the cis -[PdI 2 (NHC) 2 ] form was isolated, and its structure was determined by XRD. The stability of the possible geometrical and rotational isomers has been assessed also via DFT calculations (level of theory: COSMO-ZORA-BLYP(D3(BJ))/TZP). A second product forms along with the mononuclear complex and was identified as a dinuclear complex with the NHC and the nitrogen atom of the triazole ring bridging two trans -PdI 2 units. Finally, the nitrogen atom on the triazole ring was methylated affording a pendant triazolium salt, which can also give a carbene ligand upon deprotonation.
Related
- Quinoxaline-Triazole Hybrids: Exploring the Impact of Substituent Architecture on Cytotoxic Potency and Receptor Interaction.
- Auto‐Click Synthesis of a Copper(I) –N ‐Heterocyclic Carbene Porous Organic Polymer and Its Transmetalation to Palladium(II) for Azide–Alkyne Cycloaddition and Cross‐Coupling Reactions
- Coordination-guided design of triazole-based Cu(ii) and Pt(iv) complexes: synthesis, characterization, theoretical studies, molecular docking and anticancer activity
- Development of an Efficient Synthetic Method for Nitrogen-Containing Heterocyclic Primary Sulfonamides
- Unravelling carbene moiety role in the N-heterocyclic carbene-phosphinidenes coordination chemistry: bonding and reactivity in gold chemistry
BibTeX
@article{longhi2026palladiumii,
title = {{Palladium(II) coordination of N-heterocyclic carbene ligands with a triazole moiety in the nitrogen substituent}},
author = {Andrea Longhi and Francesca Malori and Marco Baron and Marzio Rancan and Marco Roverso and Lidia Armelao and Sara Bogialli and Laura Orian and Cristina Tubaro},
journal = {Inorganica Chimica Acta},
year = {2026},
month = oct,
doi = {10.1016/j.ica.2024.122498},
url = {https://hal.science/hal-05790957v1},
note = {CC BY},
}
RIS
TY - JOUR
TI - Palladium(II) coordination of N-heterocyclic carbene ligands with a triazole moiety in the nitrogen substituent
AU - Andrea Longhi
AU - Francesca Malori
AU - Marco Baron
AU - Marzio Rancan
AU - Marco Roverso
AU - Lidia Armelao
AU - Sara Bogialli
AU - Laura Orian
AU - Cristina Tubaro
PY - 2026
DA - 2026/10/10
JO - Inorganica Chimica Acta
DO - 10.1016/j.ica.2024.122498
UR - https://hal.science/hal-05790957v1
AB - • Synthesis and characterization of Pd(II) complexes with N-heterocyclic carbene ligands having a triazole pendant group. • Characterization of geometrical and rotational isomers for complexes of general formula [PdI 2 (NHC) 2 ]. • Evaluation of the energetics of the different isomers via DFT calculations. • Possibility to functionalize the triazole moiety affording a precursor of triazol-based N -heterocyclic carbenes. • Dinuclear complex formed by bridging coordination through the N-triazole and the C-imidazole atoms to two trans -PdI 2 units. A series of N -heterocyclic carbene (NHC) palladium complexes derived from N -methyl or N -mesityl-imidazolium salts bearing a triazole ring as pendant group to the second nitrogen atom, have been synthesized and characterized by NMR spectroscopy, mass spectrometry and single-crystal X-ray diffraction. Deprotonation of the imidazolium salt with palladium(II) acetate in acetonitrile affords square-planar Pd(II) complexes of general formula [PdI 2 (NHC) 2 ] with trans geometry. The steric hindrance of the NHC ligand substituents allows to characterize in solution both rotation syn and anti isomers. In contrast, in the crystallization process, the cis -[PdI 2 (NHC) 2 ] form was isolated, and its structure was determined by XRD. The stability of the possible geometrical and rotational isomers has been assessed also via DFT calculations (level of theory: COSMO-ZORA-BLYP(D3(BJ))/TZP). A second product forms along with the mononuclear complex and was identified as a dinuclear complex with the NHC and the nitrogen atom of the triazole ring bridging two trans -PdI 2 units. Finally, the nitrogen atom on the triazole ring was methylated affording a pendant triazolium salt, which can also give a carbene ligand upon deprotonation.
SN - 0020-1693
SN - 0020-1693
ER -